Modelling the Eurasian Ice Sheet

Conference lecture at the international conference "Glacial evolution of the north European ice sheets during the Quaternary: Status and Challenges", 15.03.24, Trondheim, Norway

Flight tests of a direct lift control system during approach and landing

Flight tests of modified aileron direct lift control system during approach and landing of F8-C aircraf

The build-up, configuration, and dynamical sensitivity of the Eurasian ice-sheet complex to Late Weichselian climatic and oceanic forcing

The Eurasian ice-sheet complex (EISC) was the third largest ice mass during the Last Glacial Maximum (LGM), after the Antarctic and North American ice sheets. Despite its global significance, a comprehensive account of its evolution from independent nucleation centres to its maximum extent is conspicuously lacking. Here, a first-order, thermomechanical model, robustly constrained by empirical evidence, is used to investigate the dynamics of the EISC throughout its build-up to its maximum configuration. The ice flow model is coupled to a reference climate and applied at 10 km spatial resolution across a domain that includes the three main spreading centres of the Celtic, Fennoscandian and Barents Sea ice sheets. The model is forced with the NGRIP palaeo-isotope curve from 37 ka BP onwards and model skill is assessed against collated flowsets, marginal moraines, exposure ages and relative sea-level history. The evolution of the EISC to its LGM configuration was complex and asynchronous; the western, maritime margins of the Fennoscandian and Celtic ice sheets responded rapidly and advanced across their continental shelves by 29 ka BP, yet the maximum aerial extent (5.48 × 106 km2) and volume (7.18 × 106 km3) of the ice complex was attained some 6 ka later at c. 22.7 ka BP. This maximum stand was short-lived as the North Sea and Atlantic margins were already in retreat whilst eastern margins were still advancing up until c. 20 ka BP. High rates of basal erosion are modelled beneath ice streams and outlet glaciers draining the Celtic and Fennoscandian ice sheets with extensive preservation elsewhere due to frozen subglacial conditions, including much of the Barents and Kara seas. Here, and elsewhere across the Norwegian shelf and North Sea, high pressure subglacial conditions would have promoted localised gas hydrate formation

A multi-source-to-sink system in a dynamic plate tectonic setting: the Cenozoic of the Barents Sea, Norwegian Arctic

Abstract of an oral presentation at the 61st British Sedimentological Resarch Group Annual Meeting, Southampton, 6-8 December 2022.When multiple source areas are located on a continuously moving plate margin relative to a sink, the signal propagation in the source-to-sink system may vary significantly in time and space. How fast and severe the impact of tectonics and climate is on sediment erosiontransfer-deposition in this dynamic setting is still not well understood. Similarly, how do we quantify the relative sediment contribution from each source area? Here, we use a forward stratigraphic modelling technique to constrain key controlling parameters in basin filling in relation to the Cenozoic successions of the Barents Sea in the Norwegian Arctic. The Cenozoic evolution of the Barents Sea shelf is strongly linked to the breakup between the Greenland and the Eurasian plates at c. 55 Ma, which led to the development of highs and basins along the margins of the Barents Sea. This configuration resulted in the deposition of progradational wedges and submarine fans (c. 40 Ma) in the Sørvestsnaget Basin. Subsequent plate reorganization caused a major shelf uplift (c. 33 Ma) and opening of the Fram Strait (c. 17 Ma) and affected the sedimentary processes and deposits in the sink (including contourites) now observable in seismic and borehole data. Moreover, Cenozoic successions were deposited under different extreme climate settings ranging from the Paleocene-Eocene Thermal Maximum (PETM) to icehouse conditions during the Quaternary glaciations (c. <2.7 Ma). A major increase in sediment supply resulting from glacial erosion is reflected in the deposition of a series of trough mouth fans along the continental margin. We present preliminary results of an ongoing project modelling this source-to-sink system, and discuss what factors control sediment erosion, transfer, and basin filling